31551120520 has 16 divisors (see below), whose sum is σ = 70990021260. Its totient is φ = 12620448192.

The previous prime is 31551120473. The next prime is 31551120571. The reversal of 31551120520 is 2502115513.

It can be written as a sum of positive squares in 2 ways, for example, as 29366305956 + 2184814564 = 171366^2 + 46742^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 394388967 + ... + 394389046.

Almost surely, 2^31551120520 is an apocalyptic number.

It is an amenable number.

31551120520 is an abundant number, since it is smaller than the sum of its proper divisors (39438900740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31551120520 is a wasteful number, since it uses less digits than its factorization.

31551120520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 788778024 (or 788778020 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 25.

The spelling of 31551120520 in words is "thirty-one billion, five hundred fifty-one million, one hundred twenty thousand, five hundred twenty".